Abstract:

In this study, inverse kinematic analysis of 3-CCC type asymmetric parallel mechanism, which is one of the 3D3A class parallel robot structures with 6 degrees of freedom, was made and two design proposals were performed. Working spaces of the proposed designs have been calculated. In the designs, CPAC (P: Active prismatic joint) leg structure provided with D4 type constraint and CPAC (A: Active rotational joint) leg structure provided with A1 type constraint were used. In addition, the CPAC (A: Active rotational joint, P: Active prismatic joint) leg structure obtained by using two active joints in a single leg was also used in the designs. This robot type is also referred to as a 3-CCC mechanism in the literature. In the first design proposal, the fixed and mobile platforms were determined to be equilateral triangles with cylindrical joints. Platforms are connected to each other by 3 CCC leg types. In the second design proposal, the movable platform with fixed cylindrical joints placed in XY, XZ and YZ planes and pointwise end-effector is connected with 3 CCC leg types. The lengths of the cylindrical joints used in the fixed and mobile platform were kept the same in both designs. While calculating the working spaces, the limit points that the end functionalist can reach were determined and the inside area was scanned at 5 mm intervals and its accessibility was checked. Working spaces are calculated by first holding the mobile platform fixed at 0o and then rotating it between -30o + 30o angles. With the results obtained, it has been seen that the working space can be expanded with different designs.

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